/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package club.dawdler.clientplug.web.session.base;

/**
 * @author jackson.song
 * @version V1.0
 * cookie相关操作 直接copy tomcat中的代码
 */
public final class CookieSupport {

	// --------------------------------------------------------------- Constants
	/**
	 * If set to true, we parse cookies strictly according to the servlet, cookie
	 * and HTTP specs by default.
	 */
	public static final boolean STRICT_SERVLET_COMPLIANCE;

	/**
	 * If true, cookie values are allowed to contain an equals character without
	 * being quoted.
	 */
	public static final boolean ALLOW_EQUALS_IN_VALUE;

	/**
	 * If true, separators that are not explicitly dis-allowed by the v0 cookie spec
	 * but are disallowed by the HTTP spec will be allowed in v0 cookie names and
	 * values. These characters are: \"()/:<=>?@[\\]{} Note that the inclusion of /
	 * depends on the value of {@link #FWD_SLASH_IS_SEPARATOR}.
	 */
	public static final boolean ALLOW_HTTP_SEPARATORS_IN_V0;

	/**
	 * If set to false, we don't use the IE6/7 Max-Age/Expires work around. Default
	 * is usually true. If STRICT_SERVLET_COMPLIANCE==true then default is false.
	 * Explicitly setting always takes priority.
	 */
	public static final boolean ALWAYS_ADD_EXPIRES;

	/**
	 * If set to true, the <code>/</code> character will be treated as a separator.
	 * Default is usually false. If STRICT_SERVLET_COMPLIANCE==true then default is
	 * true. Explicitly setting always takes priority.
	 */
	public static final boolean FWD_SLASH_IS_SEPARATOR;

	/**
	 * The list of separators that apply to version 0 cookies. To quote the spec,
	 * these are comma, semi-colon and white-space. The HTTP spec definition of
	 * linear white space is [CRLF] 1*( SP | HT )
	 */
	private static final char[] V0_SEPARATORS = { ',', ';', ' ', '\t' };
	private static final boolean[] V0_SEPARATOR_FLAGS = new boolean[128];

	/**
	 * The list of separators that apply to version 1 cookies. This may or may not
	 * include '/' depending on the setting of {@link #FWD_SLASH_IS_SEPARATOR}.
	 */
	private static final char[] HTTP_SEPARATORS;
	private static final boolean[] HTTP_SEPARATOR_FLAGS = new boolean[128];

	static {
		STRICT_SERVLET_COMPLIANCE = Boolean
				.valueOf(System.getProperty("org.apache.catalina.STRICT_SERVLET_COMPLIANCE", "false")).booleanValue();

		ALLOW_EQUALS_IN_VALUE = Boolean
				.valueOf(System.getProperty("org.apache.tomcat.util.http.ServerCookie.ALLOW_EQUALS_IN_VALUE", "false"))
				.booleanValue();

		ALLOW_HTTP_SEPARATORS_IN_V0 = Boolean.valueOf(
				System.getProperty("org.apache.tomcat.util.http.ServerCookie.ALLOW_HTTP_SEPARATORS_IN_V0", "false"))
				.booleanValue();

		String alwaysAddExpires = System.getProperty("org.apache.tomcat.util.http.ServerCookie.ALWAYS_ADD_EXPIRES");
		if (alwaysAddExpires == null) {
			ALWAYS_ADD_EXPIRES = !STRICT_SERVLET_COMPLIANCE;
		} else {
			ALWAYS_ADD_EXPIRES = Boolean.valueOf(alwaysAddExpires).booleanValue();
		}

		String fwdSlashIsSeparator = System
				.getProperty("org.apache.tomcat.util.http.ServerCookie.FWD_SLASH_IS_SEPARATOR");
		if (fwdSlashIsSeparator == null) {
			FWD_SLASH_IS_SEPARATOR = STRICT_SERVLET_COMPLIANCE;
		} else {
			FWD_SLASH_IS_SEPARATOR = Boolean.valueOf(fwdSlashIsSeparator).booleanValue();
		}

		/*
		 * Excluding the '/' char by default violates the RFC, but it looks like a lot
		 * of people put '/' in unquoted values: '/': ; //47 '\t':9 ' ':32 '\"':34
		 * '(':40 ')':41 ',':44 ':':58 ';':59 '<':60 '=':61 '>':62 '?':63 '@':64 '[':91
		 * '\\':92 ']':93 '{':123 '}':125
		 */
		if (CookieSupport.FWD_SLASH_IS_SEPARATOR) {
			HTTP_SEPARATORS = new char[] { '\t', ' ', '\"', '(', ')', ',', '/', ':', ';', '<', '=', '>', '?', '@', '[',
					'\\', ']', '{', '}' };
		} else {
			HTTP_SEPARATORS = new char[] { '\t', ' ', '\"', '(', ')', ',', ':', ';', '<', '=', '>', '?', '@', '[', '\\',
					']', '{', '}' };
		}
		for (int i = 0; i < 128; i++) {
			V0_SEPARATOR_FLAGS[i] = false;
			HTTP_SEPARATOR_FLAGS[i] = false;
		}
		for (int i = 0; i < V0_SEPARATORS.length; i++) {
			V0_SEPARATOR_FLAGS[V0_SEPARATORS[i]] = true;
		}
		for (int i = 0; i < HTTP_SEPARATORS.length; i++) {
			HTTP_SEPARATOR_FLAGS[HTTP_SEPARATORS[i]] = true;
		}

	}

	private CookieSupport() {
		// Utility class. Don't allow instances to be created.
	}

	public static final boolean isV0Separator(final char c) {
		if (c < 0x20 || c >= 0x7f) {
			if (c != 0x09) {
				throw new IllegalArgumentException("Control character in cookie value or attribute.");
			}
		}

		return V0_SEPARATOR_FLAGS[c];
	}

	public static boolean isV0Token(String value) {
		if (value == null) {
			return false;
		}

		int i = 0;
		int len = value.length();

		if (alreadyQuoted(value)) {
			i++;
			len--;
		}

		for (; i < len; i++) {
			char c = value.charAt(i);

			if (isV0Separator(c)) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Returns true if the byte is a separator as defined by V1 of the cookie spec,
	 * RFC2109.
	 *
	 * @throws IllegalArgumentException if a control character was supplied as input
	 */
	public static final boolean isHttpSeparator(final char c) {
		if (c < 0x20 || c >= 0x7f) {
			if (c != 0x09) {
				throw new IllegalArgumentException("Control character in cookie value or attribute.");
			}
		}

		return HTTP_SEPARATOR_FLAGS[c];
	}

	public static boolean isHttpToken(String value) {
		if (value == null) {
			return false;
		}

		int i = 0;
		int len = value.length();

		if (alreadyQuoted(value)) {
			i++;
			len--;
		}

		for (; i < len; i++) {
			char c = value.charAt(i);

			if (isHttpSeparator(c)) {
				return true;
			}
		}
		return false;
	}

	public static boolean alreadyQuoted(String value) {
		if (value == null || value.length() < 2) {
			return false;
		}
		return (value.charAt(0) == '\"' && value.charAt(value.length() - 1) == '\"');
	}
}
